Battle Casting( Races of the Wild, p. 148)
You have a knack for staying out of harm's way when casting spells.
Combat Casting (PH) , Concentration 5 ranks, DEX 13,
While casting a spell, you gain a +2 dodge bonus to your Armor Class. The bonus lasts until the beginning of your next turn. You cannot make attacks of opportunity while claiming the dodge bonus from this feat.